Safety lock for extractors or the like



May 16, 1933. A. H. ADAMS SAFETY LOCK FOR EXTRACTORS OR THE LIKE Filed April 12, 1928 2 Sheets-Sheet l ARTH u k H.. fi-PA Ms INVENTOR. BY A ATTORNEY I May 16, 1933. A. H. ADAMS SAFETY LOCK FOR EXTRACTORS OR THE LIKE Filed April 12, 1928 2 Sheets-Sheet 2 ARTHUR H. A Ams IN V EN TOR.

A TTORNEY Patented May 16, 1933 UNITED STA AT- M OFFICE.

ARTHUR H. ADAMS, OF LA GRANGE, ILLI OIS, Assrenon T0 ,T'ROY LAUNDRY MACHINERY company, me, on NEW Yong; N. 'Y., e conPoRA'rIon-orDE AWARE SAFETY LOCK EXTRAC'I OBS OR LIKE Application filed April 12,

This invention relates to centrifugal treatingmachines and in particular to safety a locking means for preventing the cover of an extractor or similar machine from being opened before the rotating parts are at rest.

In centrifugal treatingmachines employing rotating baskets or the like, it is requisite for reasons of safety that the attendant be unable to gain access to the interior while the basket is rotating. Various forms of automatic locks for this purpose have been devised but these prior locks have either beenmechanically complicated and ineffec- Y tive for an interval during which the basket is expending its momentum after disconnection from the driving meansor have'interfered with the proper or most convenient charging of the basket.

' Accordingly, it is a principal object of this invention to provide centrifugal extractors and similar machines with means for positively preventing access to the extractor basket while it is rotating. 1

A feature of the invention resides in a lock suitable for centrifugal extractors for retaining the extractor cover closed not only I while the driving means is connected to the extractor drum but also while the drum is rotating after disconnection from the driving means, the said lock being such that when the cover is open, the center of the basket is unobstructed and said basket maybe charged in any desired manner.

Another featureof the invention pertains to an extractor cover lock which cooperates with a novel form of brake mechanism to insure the locking of the extractor cover until the parts are at rest.

A still further feature ofthe invention is to provide a centrifugal extractor or similar machine with. safety locking mechanism which is comparatively simple in construction and efficient in use.

Other features and advantages will be apparent after a consideration ofthe follow- 19 28. 7 Serial No. 269,580.

ing detailed description and the appended" claims? i The invention will be more fully disclosed hereinafter and in theaccompanying drawings with reference to an extractorsuitable for laundry use. However, it will be understood that the :invention is ,capablevof application to other types of machines wherein a driving shaft must come to completefre'st under the action ofaa brake before asafety lock or the like is released or before almost any action is to be determined.

For the purpose of illustration, therefore, Fig; 1 shows in elevation a sufiicient portion of an extractor employing a brake and automatic lock according to the invention.

Fig. 2 isv a plan view in broken section'of V the mechanism shown in Fig. 1 with the basket removed.-

Fig. 3 is a detail study showing two positions .ofthe automatic locking means accordmg to the invention.v This figure shows the 7 locking meansinits effective and-non-efi'ective positions. 3 I l f Fig. 4 is a further study showing the locking mechanism in two other positions where-' in it is controlled by. the momentum of the drive shaft.

The same reference characters are used? to designate similar parts in the several figures of the drawings.

Referring particularly to, Fig. ,1 of the drawings,,the numeral 1 indicates the outer casing or curb of an extractor or similarmaxchine provided with a pedestal-like base 2 which is bolted'or fastened in any convenient manner to the fioorgorfoundation 3. "The central portion of the pedestal 2 asshownis hollow and serves as ahousing for the drive shaft 4t which is provided at its lower extremity with'a suitable step bearing represented schematically by the numeral 5. The

upper end of shaft ifis fastened to and supportstheextractor basket which may be of any, well knowndesign. Any suitable motor means may be employed for rotating shaft 4 and the attached basket through the intermediary of the gears 6 and 7, the former of which is attached to the motor shaft 8. For purposes hereinafter set forth, it is preferable that gears 6 and 7 be of the reversible type.

Shaft 4 is. also provided withsuitable braking mechanism, preferably of the type disclosed in copending application Serial No. 269,851 filed April 13, 1928. Said brake comprises a series of relatively thin metal discs 9, faced or separated by friction material. The discs 9 as shown in Fig. 2 are circular and splined, to the shaft 4, while the discs 10 are loose .on shaft4 and have cam shaped peripheries providing opposite ly disposed projections 11 and 12. This pile-up of discs is preferably provided with means for regulating or adjusting the amount of friction, for example, a compression spring 11 and the adjusting nut 12. It is obvious, therefore, that a positive braking action on the shaft 4 will be effected if the discs 10 are prevented from rotating due to engagement with a suitable stop bar or the like. For this purpose, there is provided a rectangular swingable' snatch-frame 13, the

end member 13 of which is adapted to latch with the projections. 11 and 12 when said frame is in its latching position. The frame 13 is swingably mounted by means of arm 14 on a spindle 14 which is fastened to the arm 15 of an offset bell-crank lever comprising the horizontally offset arms 15 and 16,

and the vertical arm 17. The bell-crank lever is mounted for rotation around a vertical axis and for this purpose-suitable bearings 18 are provided for theends 19 of the arm 17. The horizontal arm 15 carries a Vertical pin 20 which limits the independent swinging movement of the swingable frame connected at its lower end to the link 24 which in turn has its opposite'end connected to the offset arm 16 through link 29. For the purpose of holding the latch 22 in engagement with the lip 25 there is provided an electromagnet 26 which is adapted to be energized while the machine is in operation. The full lines of Fig. 2 show the latching mechanism in the running position of the machine with the swingable frame 13 attracted'by magnet 26 and abutting against the pin 20 wherebythe arm 15 is moved slightly to the left against the tension of spring 27 In this position of the frame .13

the arm. 16 is in the position indicated in 'full' lines and the latch 22 engages the lip 25.- For thepurpose of unlatching the cover the magnet 26 is deenergized and under the tension of spring 28, frame 13 is immediately swung into engagement with the discs 10 around the pin 14 as a pivot, whereupon notches 11 engage the end 13 of the frame and draw it toward the left to the position indicated by the dot-dash lines and against the tension of spring 27 The discs 10 are thus positively latched to prevent further rotation thereof and consequently exert a corresponding continuous braking effect on the shaft 4 through the intermediary of discs 9. I

For the purpose of enabling a'clear understanding to be attained of the sequence of operations of the brake controlled latch reference should be had to F gures 3 and 4.

Referring particularly to Fig. 3, the full lines represent the latching mechanism in its normal positionwherein the latch 22 is free of the lip 25 and the cover 21 may there- ;fore be raised for access to the extractor basket. In this position it will be seenthat the swingable frame 13 is held in its dovvnmost position against the discs 10 by means of spring 28, and similarly the'arm'15 of the offset bell crank is held in its straightposition under theinfiuence of spring 27. In this position the upper arm 16 of the bellcrank as well as the horiontal connecting link 29 are in their uppermost positions (as seen in Fig. 3) and'the latch 22 is in its full line position. Preferably an electric motor is used to drive the shaft 8, and as described in my above cited copending application, the means for making the source of power available to the motor at the same time renders the sourceof power available to energize the magnet 26. The frame 13 is thereupon attracted and rotates freely about the spindle 14 until it engages the pin 20 on the arm 15. Under the influence of magnet 26 the frame l3'continues to moveuntil it is completely attracted and during this latter portion of its movement it carries with it the arm 15 against the tension of spring 2'? until said arm assumes the dotted line position. During this rotation of arm 15, the arm 16 and link 29 are also rotated to their dotted posi tions effecting an engagement of latch 22 with the cover lip 25. j The mechanism remains in this position while the motive power is connected to the shaft 4.

When it is desired to bring the shaft 4 and the extractor drum to rest the circuit of magnet 26 is broken and the motive power is disconnected. Magnet 26 thereupon deenerengages the frame 13 and pulls said frame toward the left against the tension of spring 27 toits full line'position (Fig. 4) The frame 13 in moving toward the left under the influence of the shaft momentum rotates the offsetbell crank lever to the full line position in which position the latch 22 is maintained in registry with thecover lip and continues toprevent the cover being opened. The latching mechanism is retained in this position so long as the momentum of the shaft is sufficient to overcome the tension of the spring 27. As the shaft momentum dies down the spring 27 begins to take control and pulls the frame 13 and arm 15 back to the dotted iine position. During this backward movement the said frame being in engagement with the notched edges ofthe discs 10, rotates these discs in the direction of the dotted arrow. lVhen the momentum of the shaft has been completely expended the discs 10 and the latching mechanism are restored to their normal positions with'the latch 22 out of engagement with the cover lip.

In this connection it may be noted that when the shaft 1 has ceased rotating under its own momentum the spring 27 has to overcome practically only the friction of the step bearing 5 and therefore it is preferable that the gears 6 and 7 be of the reversible type.

From the foregoing it is obvious that the member 22 positively latches the cover against its being opened not only while the shaft 1 is connected to the motive power but also during the interval while the momentum of the rotating parts is dying down. Consequently the cover cannot be opened until the extractor basket is completely at rest.

While it has been chosen to illustrate specific apparatus for carrying out the invention, it will be understood that various changes may be made without departing from the spirit and scope thereof. For example, while an extractor of the vertical drum type has been disclosed it is obvious that the brake controlled latch mechanism.

may be applied to any other type of extractor.

Furthermore, while the latching mechanism is shown as electromechanically controlled, it

is within the scope of the invention to use any other form of control. For example, the usual belt sh1ft1ng mechanism may be' con nected through suitable links to the swing able frame 13 to actuate the same in place of the electromagnet 26. Furthermore, while it has been chosen to illustrate mechanism for looking a cover, it will be understood that the invention in its broad aspect is concerned with the utilization of the drag on, a brake applied to any revolving body to'determine when the momentum of such body is eX hausted and by this determination to'determine the end or the be inning of a signal, of a safety or locked condition or almost any desired step, operation or action, like the open ing of a valve, etc. that should awaitthe ex haustion of momentum in the rotating'body. While the particular form ofbrake shown is that 'disclose d in application Serial No. '4

a spring, equivalent to 27 in the drawings to said member when the momentum of V restore the revolving system is exhausted, and the dragging or pull of the brakecomes to an end. Furthermore, instead of operating the latch the mechanism disclosed may equally well operate a signal either visual or'audible'for notifying the attendant that access may be" had to the extractorbasket or admit steam for a next step in the process, etc. si0n,it will also be understood that while the invention has been disclosed in connection with acentrifugal extractor, it is capable of application to other analogous rotating ma chines.

What I claim is 1. In combination, a rotatable drum, a cover for said drum, a driving shaft for said In concludrum, a lock for said cover, a source of motive power forsaid shaft, braking mechanism for said shaft, means for actuating said lock independently of said braking mechanism,

said braking mechanism being effective to" maintain said lock actuated after disconnection of said drum from said power source.

2. In combination, a driving shaft, 2. friction brake for said shaft comprising sets'of notched friction elements, a latch member for engaging said "notches to exert a positive braking action on said shaft, and a lock for said cover operatively connected to said latch when said shaft. is disconnected from .the source of power.

3.. In an extractor, the combination of a" curb, a cover for said curb, a lock forsaid cover, an extractor basket mounted forirota tion within saidcurb, a .snatch brake for said basket, operating mechanism 7 for said lock adapt d to be actuated independently of said brake whilesaid basket is being driven and to be actuated under" control of said brake while said basket is rotating u d i own inertia I p, v 4. In combination, means for 'lock-inga cover closed comprising a friction brake, a

lock actuating mechanism, and means comprising a shiftable element for coupling said actuating means to said braking means.

' .5..In combination, an extractor basket, a cover for said basket, a lockfor said cover, lock actuating mechanismfa drivingshaft for said basket, a friction brake for said shaft, a shiftable element forexerting'a posi I tion, a rotatable basket, a driving shaft for 'tive braking action on said shaft and for coupling said lock actuating mechanism to said shaft. I I

In combination, anextractor basket, a cover for said basket,a lock for said cover, lock actuating means, a friction brake for said basket and means comprising said brake for actuating said mechanism to maintain said lock closed while said basket is rotating, said lastmentioned means being rendered ineffective only when said basket is brought to rest. 1 1 a v 7 Safety mechanism for an extractor comprising an extractor-basket, a cover, a cover lock, actuating mechanism for said lock, and friction means for exerting a positive braking action on said basket and for rendering said lock actuating mechanism effective;

8. In combination, a rotatable element, means for imparting momentum to said element, means for continuously reducing the momentum of said elementwhen disconnect ed from the first mentioned means, a con troller device to beselectively actuated by the second-mentioned means, said controller device assuming one condition while said second mentioned means is reducing the 1nomentum of said element, and assuming a different condition when said second mentioned means has reduced the momentum of said element to a ,pre-determined minimum.

9. In combination, a rotatable element, means for rotating said element, means comprising a friction brake for reducing the momentum of said element when disconnected from the first mentioned means for exerting a drag on said elemcnt,.a controller device,

and means comprising a spring effective when the momentum of said element is above a predetermined amount for holding said controller device in one condition, said last mentioned means also effective upon reduction of the momentum of said element below a predetermined minimum to change the conditlon of sald controller device.

, 10. In a centrifugal extractor, in comblnasaid basket, a source of power for rotating said basket, a friction brake for said shaft adapted gradually to stop rotation thereof, locking 'meansfor preventing access to said basket, operating means normally acting to render said brake effective and said locking means ineffective, means for controlling the action of said operating means to render said render said brake effective and said locking April 1928. V

I ARTHUR H. ADAMS.

brake ineffective and said locking means efs fective when said source of power is made available to rotate saidbasketa 11. In a centrifugal extractor, in combination, a rotatable basket, a driving shaft for a said basket, a source ofpower for rotating said basket, a friction brake for said shaft.

' adapted gradually to stop rotation thereof,

' locking meansfor preventing access to said basket, operating means normally acting to 

